LinuxQuestions.org - how to migrate an existing system with RHEL5 OS to RAID1 (problem with '/dev/root' )

I am trying to migrate my existing system with one IDE disk , tools installation already done... without loosing informations and having to install once again every things, to RAID1 (soft) with a second IDE disk

I tried to do this using somme informations given on forums but i always have a kernel Panic at the end of boot
What I did:

The system is going down for system halt NOW!
login as: root
root's password:
/usr/bin/xauth: creating new authority file /root/.Xauthority
[root ~]# df -k .
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hda1 15235040 6969416 7479244 49% /

root ~]# sfdisk -l

Disk /dev/hda: 155061 cylinders, 16 heads, 63 sectors/track
Warning: The partition table looks like it was made
for C/H/S=*/255/63 (instead of 155061/16/63).
For this listing I'll assume that geometry.
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/hda1 * 0+ 1957 1958- 15727603+ 83 Linux
/dev/hda2 1958 2479 522 4192965 82 Linux swap / Solaris
/dev/hda3 2480 9728 7249 58227592+ 83 Linux
/dev/hda4 0 - 0 0 0 Empty

[root ~]# umount /local
[root ~]# swapoff -a
[root ~]# vi /etc/mdadm.conf

DEVICE /dev/hd[ab][123]
ARRAY /dev/md0 devices=/dev/hda1,/dev/hdb1
ARRAY /dev/md1 devices=/dev/hda2,/dev/hdb2
ARRAY /dev/md2 devices=/dev/hda3,/dev/hdb3
~

[root ~]# vi /boot/grub/device.map

# this device map was generated by anaconda
(hd0) /dev/hdb
(hd1) /dev/hda

[root ~]# vi /boot/grub/grub.conf
[root ~]#
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You do not have a /boot partition. This means that
# all kernel and initrd paths are relative to /, eg.
# root (hd0,0)
# kernel /boot/vmlinuz-version ro root=/dev/hdb1
# initrd /boot/initrd-version.img
#boot=/dev/hdb
default=1
timeout=5
splashimage=(hd0,0)/boot/grub/splash.xpm.gz
hiddenmenu
title RAID Scientific Linux SL (2.6.18-194.26.1.el5PAE)
root (hd1,0)
kernel /boot/vmlinuz-2.6.18-194.26.1.el5PAE ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.26.1.el5PAE.img
title RAID Scientific Linux SL (2.6.18-194.26.1.el5)
root (hd1,0)
kernel /boot/vmlinuz-2.6.18-194.26.1.el5 ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.26.1.el5.img
title RAID Scientific Linux (2.6.18-194.3.1.el5)
root (hd1,0)
kernel /boot/vmlinuz-2.6.18-194.3.1.el5 ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.3.1.el5.img
title NON-RAID Scientific Linux SL (2.6.18-194.26.1.el5PAE)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-194.26.1.el5PAE ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.26.1.el5PAE.img
title NON-RAID Scientific Linux SL (2.6.18-194.26.1.el5)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-194.26.1.el5 ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.26.1.el5.img
title NON-RAID Scientific Linux (2.6.18-194.3.1.el5)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-194.3.1.el5 ro root=LABEL=/ selinux=0 rhgb quiet
initrd /boot/initrd-2.6.18-194.3.1.el5.img
~

[root ~]# df -k .
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hdb1 15235040 7036288 7412372 49% /
[root ~]# mdadm -C /dev/md0 --level=raid1 --raid-devices=2 --force missing /dev/hda1
mdadm: /dev/hda1 appears to contain an ext2fs file system
size=15727600K mtime=Thu Mar 3 13:56:35 2011
Continue creating array? y
mdadm: array /dev/md0 started.
[root ~]# mdadm -C /dev/md2 --level=raid1 --raid-devices=2 --force missing /dev/hda3
mdadm: /dev/hda3 appears to contain an ext2fs file system
size=58227592K mtime=Thu Mar 3 13:56:35 2011
Continue creating array? y
mdadm: array /dev/md2 started.
[root ~]# mdadm -C /dev/md1 --level=raid1 --raid-devices=2 --force missing /dev/hda2
mdadm: /dev/hda2 appears to be part of a raid array:
level=raid1 devices=2 ctime=Wed Mar 2 17:11:39 2011
Continue creating array? y
mdadm: array /dev/md1 started.

[root ~]# mkinitrd --preload=raid1 --with=raid1 --builtin=raid1 --force-scsi-probe --force-raid-probe /boot/initrd-'uname -r'-raid.img 'uname -r'
[root ~]#

[root ~]# mkswap /dev/md1
Setting up swapspace version 1, size = 4293521 kB

I modified my fstab:
01.# cat /etc/fstab
02.# /etc/fstab: static file system information.
03.#
04.#
/dev/md0 / ext3 defaults 1 1
/dev/md2 /local ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
/dev/md1 swap swap defaults 0 0
test.iso /mnt/iso udf,iso9660 noauto,loop,owner,user,rw 0 0

[root ~]# mkfs.ext3 /dev/md0
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
1966080 inodes, 3931872 blocks
196593 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4026531840
120 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 39 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root ~]#

[root ~]# mkfs.ext3 /dev/md2
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
7290880 inodes, 14556880 blocks
727844 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=0
445 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information:
done

This filesystem will be automatically checked every 38 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root ~]#
[root ~]#
[root ~]# umount /local

[root ~]# mkdir /mnt/hdb3
[root ~]# mount /dev/hdb3 /mnt/hdb3
[root ~]# mkdir /mnt/md2
[root ~]# mount /dev/md2 /mnt/md2
[root ~]# cp -dpRx /mnt/hdb3 /mnt/md2

[root ~]# mkdir /mnt/md0
[root ~]# mkdir /mnt/hdb1
[root ~]# mount /dev/md0 /mnt/md0
[root ~]# mount /dev/hdb1 /mnt/hdb1
[root ~]# cp -dpRx /mnt/hdb1/* /mnt/md0

[root ~]# grub
Probing devices to guess BIOS drives. This may take a long time.

GNU GRUB version 0.97 (640K lower / 3072K upper memory)

[ Minimal BASH-like line editing is supported. For the first word, TAB
lists possible command completions. Anywhere else TAB lists the possible
completions of a device/filename.]

grub> device (hd0) /dev/hda

grub> root (hd0,0)
Filesystem type is ext2fs, partition type 0x83

grub> setup (hd0)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd0)"... 15 sectors are embedded.
succeeded
Running "install /boot/grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/boot/grub/stage2 /boot/grub/grub.
conf"... succeeded
Done.

grub>

Boot the system

and fail with kenel panic

booting 'Raid .......
root (hd0,0)
file system type is ext2fs, partition type 0x83
Kernel /boot/vmlinuz....
..........
initrd /boot/initrd.....

Memory for crash kernel....
red Hart nash version .....
hub....
mount : could not find file system /dev/root
setuproot : moving /dev failed : no such file or directory
setuproot : error mounting /proc : no such file or directory
setuproot : error mounting /sys : no such file or directory
switchroot :mount failed : no such file or directory
kernelpanic - not syncing : attempted to kill init

Please Help...